<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <link href="./css/counter.css" rel="stylesheet">
</head>
<body>
    <div id="app">
         <div class="result"><input type="text" v-model="counter"></div>
         <div class="items">
            <div class="item" @click="counter=counter+0">0</div>
            <div class="item" @click="counter=counter+1">1</div>
            <div class="item" @click="counter=counter+2">2</div>
            <div class="item" @click="counter=counter+3">3</div>
            <div class="item" @click="counter=counter+4">4</div>
            <div class="item" @click="counter=counter+5">5</div>
            <div class="item" @click="counter=counter+6">6</div>
            <div class="item" @click="counter=counter+7">7</div>
            <div class="item" @click="counter=counter+8">8</div>
            <div class="item" @click="counter=counter+9">9</div>
        </div>
    </div>
</body>
<script>
    const counter ={
        data() {
            return {
                counter: 0
            }
        }
    }
    Vue.createApp(counter).mount('#app')
</script>

</html>